PubMed Health⌕ Search

Biomedical subjects

Qiang He

Publications and source records attributed to Qiang He.

At least 37 records · Page 2Linked to original sources

FAK signaling is critical for ErbB-2/ErbB-3 receptor cooperation for oncogenic transformation and invasion.

The overexpression of members of the ErbB tyrosine kinase receptor family has been associated with cancer progression. We demonstrate that focal adhesion kinase (FAK) is essential for oncogenic transformation and cell invasion that is induced by ErbB-2 and -3 receptor signaling. ErbB-2/3 overexpression in FAK-deficient cells fails to promote cell transformation and rescue chemotaxis deficiency. Restoration of FAK rescues both oncogenic transformation and invasion that is induced by ErbB-2/3 in vitro and in vivo. In contrast, the inhibition of FAK in FAK-proficient invasive cancer cells prevented cell invasion and metastasis formation. The activation of ErbB-2/3 regulates FAK phosphorylation at Tyr-397, -861, and -925. ErbB-induced oncogenic transformation correlates with the ability of FAK to restore ErbB-2/3-induced mitogen-activated protein kinase (MAPK) activation; the inhibition of MAPK prevented oncogenic transformation. In contrast, the inhibition of Src but not MAPK prevented ErbB-FAK-induced chemotaxis. In migratory cells, activated ErbB-2/3 receptors colocalize with activated FAK at cell protrusions. This colocalization requires intact FAK. In summary, distinct FAK signaling has an essential function in ErbB-induced oncogenesis and invasiveness.

Animals↗

[Influence of pre-transplant serum level of soluble CD30 on the long-term survival rates of kidney transplant recipients and grafts].

OBJECTIVE: To investigate the influence of pre-transplant sCD30 level on the long-term survival rates of kidney transplant recipients and grafts among Chinese. METHODS: A retrospective cohort of 707 patients undergoing cadaver renal transplants between Dec.1998 and Aug 2003, 467 males and 240 females, aged 40 +/- 11, with their blood samples preserved was studied. The plasma levels of sCD30 were determined by ELISA. RESULTS: The 5-year graft survival/functional rates of the high sCD30 group were 77.7% +/- 3.5%/85.0% +/- 3.2%, significantly lower than those of the low and intermediate groups, 84.7% +/- 2.1%/98.9% +/- 1.1% and 88.1% +/- 2.9%/95.1% +/- 1.6% respectively (all P < 0.05). The 5-year recipient survival rate of the intermediate sCD30 group was 92.4% +/- 1.6%, higher than those of the low and high sCD30 groups, 84.7% +/- 3.9% and 87.1% +/- 2.7% respectively with a significant difference between the intermediate and high sCD30 groups (P = 0.032). CONCLUSIONS: Pre-transplant serum level of sCD30 reflects the immune status. Recipients with high sCD30 are prone to rejection while those with low sCD30 are prone to infections.

Adult↗

Characterization and expression analysis of bactericidal permeability-increasing protein (BPI) antimicrobial peptide gene from channel catfish Ictalurus punctatus.

Antimicrobial peptides are important components of host defenses against microbial invasions. Bactericidal permeability-increasing protein (BPI) is an antimicrobial peptide belonging to the lipid transfer/LPS-binding protein family. It serves important roles in defending against Gram-negative bacteria in the innate immune system. Here we report cloning of complete BPI cDNA from channel catfish (Ictalurus punctatus) by 5' RACE after obtaining the partial BPI cDNA sequence from EST analysis. The channel catfish BPI cDNA is 1640 bp in length with a 1428-bp open reading frame that encodes a protein of 475 amino acids. Catfish BPI gene shows high similarity with the BPI/LBP gene isolated from other teleost fish. As part of ongoing efforts in comparative genome analysis, we have assigned the catfish BPI gene to bacterial artificial chromosome (BAC) clones. Southern blot analysis on multiple BPI BAC clones indicated the presence of a single copy of the BPI gene in the catfish genome. Reverse transcription-polymerase chain reaction (RT-PCR) analysis on healthy tissues showed that BPI was expressed in a wide range of tissues including head kidney, gill, skin, trunk kidney, brain, intestine, liver, muscle, ovary, spleen and stomach. The BPI gene was not developmentally expressed until 48 h after fertilization. Quantitative real time PCR (QRT-PCR) analysis indicated that the BPI gene expression was induced after challenge with Edwardsiella ictaluri, the causative agent of enteric septicemia of catfish (ESC). BPI upregulation peaked 3 days after challenge, mirroring the expression pattern of inflammatory chemokines in catfish, suggesting that it plays a role in the innate defense response.

Amino Acid Sequence↗

[Epidemiology of cardiovascular risk in Chinese chronic kidney disease patients].

OBJECTIVE: To identify the risk factors associated with cardiovascular disease (CVD) in Chinese chronic kidney disease (CKD) patients. METHODS: As part of a multicenter Chinese cohort study, the clinical data associated with CVD of 1239 patients with CKD (stage 2 - 5) hospitalized in 7 grade 3A hospitals distributed in 5 regions of China 2002 - 2003 were collected. Logistic regression model was used to analyze the association between CVD and the demographic variables, lifestyle, medical history, medication, physical examination, and laboratory variables. RESULTS: (1) Increase of serum C-reactive protein (CRP, cut off > 10 mg/L) was an independent risk factor for development of coronary artery disease (CAD) (OR 2.13; 95% confidence interval [CI], 1.32 - 3.43). 21.5% of the patients in this group showed a value of CRP > 10 mg/L. (2) Being female, anemia, and systolic hypertension were the major determinants of the development of left ventricular hypertrophy (OR 2.99, CI 2.09 - 4.26; OR 2.66, CI 1.19 - 3.57; and OR 1.02, CI 1.00 to -1.02). 54.2% of the patients in this group had their systolic pressure controlled under 140mmHg, and only 15% of the patients in this group had their hemoglobin remain at the level >or= 110 g/L. (3) There was a significant interaction between the calcium-phosphate product and congestive heart failure (CHF) (OR 1.023, CI 1.01 - 1.03). 25.9% of the patients in this cohort had their calcium-phosphate product >or= 55. (4) Hypoalbuminemia (OR 6.01, CI 1.25 - 28.96) and diastolic hypertension (OR 1.05, CI 1.00 - 1.09) played major role in determining cerebrovascular accidents (CVA). In these cohort the prevalence of hypoalbuminemia was 37.3%. (5) Diabetes was associated with CAD (OR 2.34), CHF (OR 1.97), and CVA (OR 4.40), although its prevalence was lower in Chinese CKD patients (20%). Age was the risk factors of CAD (OR 1.04) and CVA (OR 1.22). Hypertension was associated with LVH (OR 1.016), CHF (OR 1.02), and CVA (OR 1.04). CONCLUSION: CKD is associated with nontraditional risk factors for the development of CVD, including chronic inflammation, malnutrition and calcium-phosphate disorders. Particular care must be taken to give optimal treatment for the most important CVD risk factors active in Chinese CKD patients, e.g. anemia and hypertension.

Adult↗

[Cardiovascular disease in Chinese chronic renal insufficiency patients-epidemiology survey].

OBJECTIVE: Cardiovascular (CV) disease (CVD) is the single most important cause of death among Chinese dialysis patients, accounting for 51% of overall mortality. The study was performed to investigate the prevalence and the spectrum of CVD in Chinese chronic kidney disease (CKD) patients. METHODS: The multicenter Chinese cohort study examined 1239 CKD patients from 7 main medical centers (distributed in 5 regions of China) who were hospitalized between 2002 and 2003. RESULTS: (1) The most prevalent pathological form of CVD was left ventricular (LV) hypertrophy (LVH), accounting for 58.5% of total patients. The prevalence of coronary artery disease (CAD), congestive heart failure (CHF), and cerebrovascular accidents (CVA) was 16.5%, 27.7% and 5.6%, separately. (2) The cohort with minor renal dysfunction (stage 2-3) had higher prevalence of CAD (5.9%) and CVA (1.0%) compared with general population in the same regions. Up to 41.2% of minor CKD patients were complicated with LVH, and 13.8% of them had clinical evidence of CHF. The prevalence of CAD, LVH and CHF increased as glomerular filtration decline. (3) The prevalence of CAD (20.0%) was much lower and the prevalence of CVA (5.4%) was higher in Chinese dialysis patients than that in American dialysis population. There was significant geographical variations in CAD prevalence, but it was not different between genders. CONCLUSION: The CV risk is significantly increased in patients with CKD. Even minor CKD has a major impact on the CV risk. The prevalence of CAD in Chinese dialysis patients is markedly lower than that in American dialysis population.

Adult↗

Tumor vaccine against recurrence of hepatocellular carcinoma.

AIM: To investigate the effects of autologous tumor vaccine on recurrence of hepatocellular carcinoma (HCC). METHODS: Sixty patients with HCC who had undergone curative resection, were randomly divided into HCC vaccine group and control group. Three vaccinations at 2-wk intervals were performed after curative hepatic resection. Delayed-type- hypersensitivity (DTH) test was performed before and after vaccination. Primary endpoints were the time of recurrence. RESULTS: Four patients in control group and 6 patients in HCC vaccine group were withdrawn from the study. The vaccine containing human autologous HCC fragments showed no essential adverse effect in a phase II clinical trial and 17 of 24 patients developed a DTH response against the fragments. Three of 17 DTH-positive response patients and 5 of 7 DTH-negative response patients had recurrences after curative resection. After the operation, 1-, 2- and 3-year recurrence rates of HCC vaccine group were 16.7%, 29.2% and 33.3%, respectively. But, 1-, 2- and 3-year recurrence rates of the control group were 30.8%, 53.8% and 61.5%, respectively. The time before the first recurrence in the vaccinated patients was significantly longer than that in the control patients (P < 0.05). CONCLUSION: Autologous tumor vaccine is of promise in decreasing recurrence of human HCC.

Adult↗

[The influence of early vascular rejection on late rejection in first cadaveric renal transplantation].

OBJECTIVE: To explore the influence of early completely reversal vascular rejection on late rejection. METHODS: The data of 1062 patients who received their first cadaveric transplants between May 1988 and March 2003 were analyzed respectively. The patients were divided into 2 groups: group with vascular rejection occurring within 1 month postoperatively (n = 45), and group without vascular rejection (n = 1017). Follow up was performed for at least 6 months. The influence of demographic characteristics (transplant age, sex), transplant variables (complement dependent cytotoxicity test, cold/warm ischemia time), and post-transplant variables (immunosuppressive agents for the prevention of acute rejection,) were analyzed. RESULTS: There were no differences in the age at transplantation, sex, complement dependent cytotoxicity test, cold/warm ischemia time, immunosuppression agent protocol, and serum creatinine during follow-up between the recipients of these two groups. Late rejection, including acute interstitial rejection, borderline rejection, and chronic rejection, occurring one month after transplantation was 2.22% (1/45) in the vascular rejection group, significantly lower than that of the no vascular rejection group (12.59%, 128/1017, P = 0.034) CONCLUSION: Early completely reversal vascular rejection can reduce the rate of late rejection.

Adult↗

Hydrolysis reaction analysis of L-alpha-distearoylphosphatidylcholine monolayer catalyzed by phospholipase A2 with polarization-modulated infrared reflection absorption spectroscopy.

The hydrolysis reaction of L-alpha-distearoylphosphatidylcholine (DSPC) monolayers catalyzed by phospholipase A2 (PLA(2)) has been studied using polarization-modulated infrared reflection absorption spectroscopy (PM-IRRAS) with film balance measurements. The PM-IRRAS analysis provides quantitative information about the reaction efficiency at different surface pressures. It was found that the reaction efficiency of L-DSPC monolayer hydrolysis catalyzed by PLA(2) decreased with increasing surface pressure. At zero pressure (lift-off point), the hydrolysis reaction efficiency has the highest value of 45%. Increasing surface pressure leads to the decrease of the hydrolysis efficiency. Since the surface pressure is above 20 mN/m, the hydrolysis reaction nearly stopped. PM-IRRAS technique provides a powerful means to study the hydrolysis process catalyzed by phospholipase A2 at the air/water interface.

Hydrolysis↗

[Selective expansion of human natural killer cells].

BACKGROUND & OBJECTIVE: Natural killer (NK) cells have strong potential of killing tumor cells, but it is difficult to expand sufficient NK cells to satisfy the treatment of tumor. This study was to explore the feasibility of efficiently expand NK cells through co-culturing peripheral blood mononuclear cells (PBMCs) and Wilms tumor cell line HFWT. METHODS: PBMCs and HFWT cells were co-cultured to expand NK cells. The cytotoxicity of NK cells was measured using 51Cr release assay and crystal violet (CV) staining. The proportions of CD3(+), CD4(+), CD8(+), CD16(+), and CD56(+) cells were detected using flow cytometry. RESULTS: When PBMCs were co-cultured with irradiated HFWT cells for 10-21 days, NK cells were selectively expanded; the proportion of CD56(+)/CD16(+) cells was over 50%. The NK cells killed more than 80% of fresh HFWT cells at an effector/target ratio of 2. The expansion of NK cells required continuous stimulation of PBMCs by HFWT cells. CONCLUSION: HFWT cells can effectively stimulating PBMCs to sensitively expand human NK cells for adoptive immunotherapy of human tumors.

CD3 Complex↗

[Use of autologous tumor vaccine in preventing recurrence of hepatocellular carcinoma].

OBJECTIVE: To evaluate the effects of autologous tumor vaccines in preventing recurrences of hepatocellular carcinoma (HCC). METHODS: From March 1999 to June 2003, 80 patients with HCC undergoing resections were randomly assigned into a tumor vaccine group (n=40) and a control group (n=40). Tumor vaccines, consisting of formalin-fixed HCC tissue fragments, biodegradable sustained-releasers of granulocyte-macrophage-colony stimulating factor, interleukin-2, and an adjuvant, were developed. Every vaccine group patient received 3 vaccinations at a 2-week interval and the control group just received the adjuvant. Delayed-type-hypersensitivity (DTH) test and recurrent rates were analyzed. RESULTS: Eight patients of the vaccine group and five patients of the control group were lost in the follow-up. Thirty-two patients completed the tumor vaccine procedure and no essential adverse effects occurred. 23/32 patients developed DTH responses against the fragments of HCC. The follow-up averaged 34.3 months (from 15 to 55 months). 1-, 2-, 3-year recurrence rates of the vaccine group were 12.6%, 35.9% and 54.0%, respectively; 1-, 2-, 3-year recurrence rates of the control group were 31.6%, 61.3% and 72.1%, respectively. The recurrent rate was significantly better in the tumor vaccine group than in the control group (P = 0.037). CONCLUSIONS: Autologous tumor vaccine is a promising adjunctive modality to prevent recurrence of human HCC.

Adult↗

[Pediatric renal transplantation: clinical analysis of 23 cases].

OBJECTIVE: To study the clinical characters and the therapeutic experience of pediatric kidney transplantation. METHODS: Clinical data of 23 pediatric renal transplant recipients (less than 18 years, 14 boys, 9 girls) were analyzed. Recipients were 11 - 17 (mean 15.4 +/- 1.0 years) years old at transplantation. The kidneys were transplanted en bloc extraperitoneally into the recipient's iliac fossa, with the donor renal vein anastomosed to the recipient's external iliac vein. Among 23 transplant procedures, the donor renal artery was anastomosed to the external iliac artery in 14 cases, to the internal iliac artery in 4 cases and to the common iliac artery in 3. The other two allografts were unusual. All the patients were treated with cyclosporine or tacrolimus based immunosuppression, including steroid and azathioprine or mycophenolate mofetil. The initial dose of cyclosporine was 6 - 7 mg per kilogram of body weight per day and that of tacrolimus was 0.15 - 0.20 mg per kilogram of body weight per day. The data of the recovery of renal function, rejection episodes, incidences of side effect and related complication were analyzed respectively. RESULTS: The transplantation operations were performed uneventful in all the 23 recipients. There were no graft losses for technical reasons. The single graft failure was the result from bad compliance. The renal function was improved 5.5 days in average after transplantation in 22 cases. Main complications were arterial hypertension (57%), pulmonary infection (13%), drug-induced hepatic injury (13%) and bone marrow suppression (13%). Acute rejection occurred in 4 persons 1 year post-operatively (17%). The body weight of the recipients increased 2.3 kg in average and height increased 1.0 cm after the first post-operative year. The mean duration for follow-up was 42 month. One-year patient/graft survival rate was 100%/96% and three-year patient/graft survival rate was 90%/80%. CONCLUSION: Kidney transplantation is the preferred treatment for end stage renal failure in children patient. The well procedure, reasonable immunosuppressive regime, prevention and prompt therapy of complication are the keys to get satisfactory survival rate of human/kidney.

Adolescent↗

Expansion and activation of natural killer cells from PBMC for immunotherapy of hepatocellular carcinoma.

AIM: To induce efficient expansion of natural killer (NK) cells from peripheral blood mononuclear cells (PBMCs) using a culture of anchorage-dependent Wilms tumor cell lines, and to provide a reliable supply for adoptive immunotherapy of hepatocellular carcinoma. METHODS: Culture expansion of NK cells was achieved using PBMCs cultured with Wilms tumor cells. Cytotoxicity was measured using a standard (51)Cr release assay and crystal violet staining technique. The proportions of CD3+, CD4+, CD8+, CD16+, and CD56+ cells were determined by flow cytometry. RESULTS: After PBMCs from healthy donors and hepatocellular carcinoma (HCC) were cultured with irradiated HFWT cells for 10-21 d, CD56+ CD16+ cells shared more than 50% of the cell population, and more than 80% of fresh HFWT cells were killed at an effector/target ratio of 2 over 24 h. NK-enriched lymphocyte population from HCC patients killed HCC-1 and 2 cells with sensitivities comparable to fresh TKB-17RGB cells. HCC cells proliferated 196-fold with the irradiated HFWT cells at 18 d. Stimulation by HFWT cells required intimate cell-cell interaction with PBMC. However, neither the soluble factors released from HFWT cells nor the fixed HFWT cells were effective for NK expansion. The lymphocytes expanded with IL-2 killed fresh HFWT target cells more effectively than the lymphocytes expanded with the 4-cytokine cocktail (IL-lbeta, IL-2, IL-4 and IL-6). IL-2 was the sole cytokine required for NK expansion. CONCLUSION: Wilms tumor is sensitive to human NK cells and is highly efficient for selective expansion of NK cells from PBMCs.

Animals↗

The generation of high biomass from chlororespiring bacteria using a continuous fed-batch bioreactor.

A continuous fed-batch reactor system was developed to rapidly obtain dense chlororespiring cultures of Anaeromyxobacter dehalogenans strain 2CP-C. A syringe pump continuously delivered concentrated 2,6-dichlorophenol (50-150 mM) to an anaerobic reactor vessel at a rate that sustained linear growth but prevented the substrate toxicity of chlorophenol. Dechlorination was not significantly inhibited by end product phenol up to 8 mM. A cell density of 76.8 mg protein l(-1) was obtained in 24 h. Specific growth rates averaged 0.033 h(-1)at 50% substrate limitation, which was in agreement with the maximum specific growth rate of 0.068 h(-1). This reactor system provides an efficient, cost-effective, and convenient method to rapidly obtain dense dechlorinating biomass and is promising to accelerate investigations of enzymes involved in chlororespiration.

Anaerobiosis↗

Phase II randomized trial of autologous formalin-fixed tumor vaccine for postsurgical recurrence of hepatocellular carcinoma.

PURPOSE: We conducted a Phase II clinical trial with randomized patients to determine whether autologous formalin-fixed tumor vaccine (AFTV) protects against postsurgical recurrence of hepatocellular carcinoma (HCC). EXPERIMENTAL DESIGN: Forty-one patients with HCC who had undergone curative resection were randomly allocated to the vaccine treatment (n = 19) or no adjuvant control group (n = 22). Three intradermal vaccinations were administered at 2-week intervals beginning 4-6 weeks after hepatic resection. A delayed-type hypersensitivity test was performed before and after vaccination. Primary and secondary end points are recurrence-free survival and overall survival, respectively. Observation continued until the majority of surviving patients had lived >12 months after the curative resection. RESULTS: In a median follow-up of 15 months, the risk of recurrence in vaccinated patients was reduced by 81% (95% confidence interval, 33-95%; P = 0.003). Vaccination significantly prolonged the time to first recurrence (P = 0.003) and improved recurrence-free survival (P = 0.003) and overall survival rates (P = 0.01). AFTV played a significant role in preventing recurrence in patients with small tumors. Adverse effects were limited to grade 1 or 2 skin toxicities such as erythema, dry desquamation, and pruritus. CONCLUSIONS: AFTV therapy is a safe, feasible, and effective treatment for preventing postoperational recurrence of HCC. Patients with low tumor burdens benefit from the treatment. This treatment should be advanced to a large-scale randomized trial.

Aged↗

Acetate threshold concentrations suggest varying energy requirements during anaerobic respiration by Anaeromyxobacter dehalogenans.

Acetate threshold concentrations were determined under chlororespiring and Fe(III)-reducing conditions for Anaeromyxobacter dehalogenans strain 2CP-C. The acetate threshold concentrations measured were 69 +/- 4, 19 +/- 8, and <1 nM for chlororespiration, amorphous Fe(III) reduction, and Fe(III) citrate reduction, respectively. Residual DeltaG values of -75.4 kJ/mol of electrons for chlororespiration and -41.5 kJ/mol of electrons for amorphous Fe(III) reduction were calculated at the acetate threshold concentration. By comparing threshold concentrations for different metabolisms in a single organism, this study provides insight into the metabolic use of energy under different growth conditions.

Acetates↗

Highly flexible polyelectrolyte nanotubes.

A pressure-filter-template approach was employed to prepare polyelectrolyte nanotubes through layer-by-layer deposition in the alumina template. With the thicker wall, the ordered polymer nanotubes possess a high flexibility. The results demonstrate that the electrostatic interactions of polyelectrolytes play a key role in fabricating water-soluble charged polymer nanotubes. The structure of the polyelectrolyte nanotube was confirmed by SEM, TEM, and UV, respectively.

Journal Article↗

Direct observations of the cleavage reaction of an L-DPPC monolayer catalyzed by phospholipase A2 and inhibited by an indole inhibitor at the air/water interface.

The enzymatic hydrolysis of an L-dipalmitoylphosphatidylcholine (L-DPPC) monolayer at the air/water interface, catalyzed by phospholipase A(2) (PLA(2)), serves as a model for biospecific interfacial reactions. The cleavage of L-DPPC was investigated by Brewster angle microscopy. Different types of domain defects were observed to form in the coexisting liquid expanded and liquid condensed phases during the hydrolysis reaction. The adsorption of the enzyme was quantitatively recorded as the increase of the surface pressure over a fixed molecular area with time. In the case of L-DPPC, the surface pressure first increases and then starts to decrease, which indicates that a soluble product (lysolipid) is produced during the catalytic cleavage reaction. The increase and decrease of the surface pressure, which corresponds to the change of shape and number density of domains, indicated the occurrence of the following processes: adsorption of PLA(2), cleavage reaction, and rearrangement of substrate and product molecules at the interface. Addition of a PLA(2) inhibitor to the lipid monolayer leads to a fast surface pressure increase after enzyme injection. The surface pressure reaches a maximum value and then does not change for a long time. During this period, no change in the domain shape and number density was observed, which indicates that the enzyme is inhibited for a certain period of time. The experimental results provide the possibility of a direct way to prove inhibitor activity.

1,2-Dipalmitoylphosphatidylcholine↗